Δαφνη Ευτυχια Αρθουρος

If the past tense is used in a subordinate clause where the past tense also appears in the dominant clause, it indicates that the subordinate-clause action is happening *further* in the past than the action in the dominant clause. :)

Whoa... that does seem like a useful construct to have at times, but I'll bet it causes a lot of confusion for people learning the language. It would sure hose me. :-)